Having a pressure washer can help you easily clean up a variety of messes without having to scrub everything by hand.

If you’re going to pressure wash clients’ homes for them, you need to ensure you have a water tank, though. You never know if water on their property will have a strong enough pressure to get the job done, so a tank will ensure success. 

Can you attach a tank to your pressure washer?

As long as the pressure washer has an inlet hose that’s compatible with the water tank’s outlet, you’ll be able to use it.

While being convenient, a water tank also ensures that you have a flow of water that’s constantly running through the pressure washer, therefore preventing it from getting damaged.

With that in mind, let’s look at everything you need to know when choosing the right size water tank for your pressure washer.

Tips When Buying And Using A Water Tank For Pressure Washer

pressure wash trailer
  • Before buying a water tank for your pressure washer, always make sure that the tank will be able to provide the amount of gallons per minute that are specified for your pressure washer.
  • Before you use a water tank with your pressure washer, make sure that you’ve installed a pressure washer filter. The water entering the machine from the tank will be dirty, which can clog or damage your machine.
  • Generally, you will need an extra pump between the tank and pressure washer if the current pressure is not enough. If you can see that the water pressure you’re getting isn’t strong enough, using a regular water pump will help to increase it.

How Many Gallons Do You Need For Power Washing A House?

power washing house

The capacity of the water tank will depend on what tasks you’re doing as well as how long you’re going to be using the pressure washer.

The longer the amount of time, the larger your water tank should be so it won’t run out during your work.

Generally, power washing a house will take about 30 minutes to two hours. Smaller homes that are around 1,300 square feet in size can usually be completed within 30 minutes.

A 250-gallon water tank will be enough for that but not if your cleaning task is two hours or longer. If your cleaning task will take over two hours, then you should aim to get a tank that’s over 250 gallons to ensure you have enough.

You should take into account the pressure washer’s PSI (Pounds Per Square Inch) and GPM (gallons per minute) as these are important. A commercial medium-duty pressure washer will have between 2,600 and 3,100 PSI and will use 2.5 gallons of water per minute.

If you’re using this machine for 30 minutes, you’ll need to ensure you have around 75 gallons of water in the tank. On the other hand, a commercial heavy-duty pressure washer will have between 3,200 and 4,000 PSI and use three to four gallons per minute.

If it uses four gallons per minute and you’re using it for 30 minutes, then you’ll need 120 gallons of water in the tank.

This example should help you figure out how large your water tank should be. 

How To Connect A Water Tank To A Pressure Washer

  1. When connecting the water tank to the pressure washer, first check for the banjo fitting on the water tank.
  2. Connect a threaded pipe to the fitting, then connect an inline to the PVC before using teflon tape to secure it.
  3. Connect the ball valve and barb connector, then attach your hose to it. The barb connector needs to be clamped securely so that you won’t have water leaking from the hose.
  4. Connect the hose to your pressure washer feed line.

Why Are You Not Getting Enough Pressure?

low pressure

If you’ve connected your water tank to your pressure washer and you’re not getting the pressure you need, you should check some things.

For starters, check that the hose connections are tight and that the tank’s water faucet has been turned on. Then, check that the spray wand has not been set to a low or no-pressure mode. If it has, adjust it.

Related Questions

Can your pressure washer use water from a lake?

While this might seem like a good idea, it doesn’t usually work. If you want to try it, you will require a pressure washer that is compatible with a suction hose. However, there are impurities from the water so you’ll need a filter.

Can you connect a pressure washer to a rain barrel?

If your rain barrel has an outlet located at the bottom, this makes it possible for you to connect a hose or suction hose to it so you can connect it to a small pressure washer. But, the pressure needs to be high enough for the pressure washer.


Connecting your pressure washer to a water tank is an important part of providing professional and reliable service to clients.

You can’t always rely on the use of water at the client’s home. Having your own water tank ensures that you will always have enough water you need to complete your job and not waste time.

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